原生生物miRNA的系统鉴定与起源分析

miRNA（microRNA）是一种真核生物特有的小非编码RNA，在转录后水平行使重要的调控功能，然而miRNA的起源问题一直没有解决。原生生物是最原始的真核生物类群，其中蕴含着丰富的基因资源，但原生生物界中关于miRNA的研究存在矛盾和争议。我们先前研究发现，原生生物的miRNA与高等生物在特征上存在较大差异，不能采用高等动、植物中miRNA的标准进行研究。因此，我们总结了原生生物miRNA的三大特征，并根据这些特征设计了专门的计算机识别软件。在此基础上，本项目选取了一批代表性原生生物，采用高通量测序技术获得它们的小RNA转录组数据，选取合适的模型参数进行miRNA基因预测、表达分析、功能分析，最终获得这些miRNA之间的进化关系。本项目为研究原生生物非编码小RNA提供有力工具，为最终解决miRNA的起源与进化问题提供证据。

MiRNA(MicroRNA) is a type of eukaryote-specific small non-coding RNA which play important regulatory role in the post-transcriptional level, the origin and evolution problem is a long-standing mystery in miRNA study. The protists is the most original eukaryotic taxa, Which contains a rich genetic resources. However, there are many contradictions and disputes in protisit miRNA studies. In the previous study we found that there are significant differences in the characteristics of miRNAs in protists and higher organisms, therefore, current standards used for higher animals and plants miRNA identification are not suitiable for protists. Therefore, we summarized three major characteristics of protist miRNAs, and designed spcial software according to these characteristics. On the basis of it, we select a series of representative protists, through high-throughput sequencing technology to obtain small RNA transcriptome data, select appropriate model parameters to perform the predictions, expression analysis and function analysis of miRNA genes, ultimately get the evolution relationship between these miRNAs. This project will provide a powerful tool for the study of protist miRNAs and shed light on questions regarding the origins and evolution of miRNA in early eukaryotes.